<?php

// +----------------------------------------------------------------------

// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]

// +----------------------------------------------------------------------

// | Copyright (c) 2006-2013 http://thinkphp.cn All rights reserved.

// +----------------------------------------------------------------------

// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )

// +----------------------------------------------------------------------

// | Author: liu21st <liu21st@gmail.com>

// +----------------------------------------------------------------------

namespace Think\Db\Driver;

use Think\Db;

defined('THINK_PATH') or exit();

/**

 * MSsql数据库驱动 要求sqlserver2005

 */

class Mssql extends Db{

    protected $selectSql  =     'SELECT T1.* FROM (SELECT thinkphp.*, ROW_NUMBER() OVER (%ORDER%) AS ROW_NUMBER FROM (SELECT %DISTINCT% %FIELD% FROM %TABLE%%JOIN%%WHERE%%GROUP%%HAVING%) AS thinkphp) AS T1 %LIMIT%%COMMENT%';

    /**

     * 架构函数 读取数据库配置信息

     * @access public

     * @param array $config 数据库配置数组

     */

    public function __construct($config=''){

        if ( !function_exists('mssql_connect') ) {

            E(L('_NOT_SUPPERT_').':mssql');

        }

        if(!empty($config)) {

            $this->config	=	$config;

            if(empty($this->config['params'])) {

                $this->config['params'] =   array();

            }

        }

    }



    /**

     * 连接数据库方法

     * @access public

     */

    public function connect($config='',$linkNum=0) {

        if ( !isset($this->linkID[$linkNum]) ) {

            if(empty($config))	$config  =  $this->config;

            $pconnect   = !empty($config['params']['persist'])? $config['params']['persist']:$this->pconnect;

            $conn = $pconnect ? 'mssql_pconnect':'mssql_connect';

            // 处理不带端口号的socket连接情况

            $sepr = IS_WIN ? ',' : ':';

            $host = $config['hostname'].($config['hostport']?$sepr."{$config['hostport']}":'');

            $this->linkID[$linkNum] = $conn( $host, $config['username'], $config['password']);

            if ( !$this->linkID[$linkNum] )  E("Couldn't connect to SQL Server on $host");

            if ( !empty($config['database'])  && !mssql_select_db($config['database'], $this->linkID[$linkNum]) ) {

                E("Couldn't open database '".$config['database']);

            }

            // 标记连接成功

            $this->connected =  true;

            //注销数据库安全信息

            if(1 != C('DB_DEPLOY_TYPE')) unset($this->config);

        }

        return $this->linkID[$linkNum];

    }



    /**

     * 释放查询结果

     * @access public

     */

    public function free() {

        mssql_free_result($this->queryID);

        $this->queryID = null;

    }



    /**

     * 执行查询  返回数据集

     * @access public

     * @param string $str  sql指令

     * @return mixed

     */

    public function query($str) {

        $this->initConnect(false);

        if ( !$this->_linkID ) return false;

        $this->queryStr = $str;

        //释放前次的查询结果

        if ( $this->queryID ) $this->free();

        N('db_query',1);

        // 记录开始执行时间

        G('queryStartTime');

        $this->queryID = mssql_query($str, $this->_linkID);

        $this->debug();

        if ( false === $this->queryID ) {

            $this->error();

            return false;

        } else {

            $this->numRows = mssql_num_rows($this->queryID);

            return $this->getAll();

        }

    }



    /**

     * 执行语句

     * @access public

     * @param string $str  sql指令

     * @return integer

     */

    public function execute($str) {

        $this->initConnect(true);

        if ( !$this->_linkID ) return false;

        $this->queryStr = $str;

        //释放前次的查询结果

        if ( $this->queryID ) $this->free();

        N('db_write',1);

        // 记录开始执行时间

        G('queryStartTime');

        $result	=	mssql_query($str, $this->_linkID);

        $this->debug();

        if ( false === $result ) {

            $this->error();

            return false;

        } else {

            $this->numRows = mssql_rows_affected($this->_linkID);

            $this->lastInsID = $this->mssql_insert_id();

            return $this->numRows;

        }

    }



    /**

     * 用于获取最后插入的ID

     * @access public

     * @return integer

     */

    public function mssql_insert_id() {

        $query  =   "SELECT @@IDENTITY as last_insert_id";

        $result =   mssql_query($query, $this->_linkID);

        list($last_insert_id)   =   mssql_fetch_row($result);

        mssql_free_result($result);

        return $last_insert_id;

    }



    /**

     * 启动事务

     * @access public

     * @return void

     */

    public function startTrans() {

        $this->initConnect(true);

        if ( !$this->_linkID ) return false;

        //数据rollback 支持

        if ($this->transTimes == 0) {

            mssql_query('BEGIN TRAN', $this->_linkID);

        }

        $this->transTimes++;

        return ;

    }



    /**

     * 用于非自动提交状态下面的查询提交

     * @access public

     * @return boolen

     */

    public function commit() {

        if ($this->transTimes > 0) {

            $result = mssql_query('COMMIT TRAN', $this->_linkID);

            $this->transTimes = 0;

            if(!$result){

                $this->error();

                return false;

            }

        }

        return true;

    }



    /**

     * 事务回滚

     * @access public

     * @return boolen

     */

    public function rollback() {

        if ($this->transTimes > 0) {

            $result = mssql_query('ROLLBACK TRAN', $this->_linkID);

            $this->transTimes = 0;

            if(!$result){

                $this->error();

                return false;

            }

        }

        return true;

    }



    /**

     * 获得所有的查询数据

     * @access private

     * @return array

     */

    private function getAll() {

        //返回数据集

        $result = array();

        if($this->numRows >0) {

            while($row = mssql_fetch_assoc($this->queryID))

                $result[]   =   $row;

        }

        return $result;

    }



    /**

     * 取得数据表的字段信息

     * @access public

     * @return array

     */

    public function getFields($tableName) {

        $result =   $this->query("SELECT   column_name,   data_type,   column_default,   is_nullable

        FROM    information_schema.tables AS t

        JOIN    information_schema.columns AS c

        ON  t.table_catalog = c.table_catalog

        AND t.table_schema  = c.table_schema

        AND t.table_name    = c.table_name

        WHERE   t.table_name = '$tableName'");

        $info   =   array();

        if($result) {

            foreach ($result as $key => $val) {

                $info[$val['column_name']] = array(

                    'name'    => $val['column_name'],

                    'type'    => $val['data_type'],

                    'notnull' => (bool) ($val['is_nullable'] === ''), // not null is empty, null is yes

                    'default' => $val['column_default'],

                    'primary' => false,

                    'autoinc' => false,

                );

            }

        }

        return $info;

    }



    /**

     * 取得数据表的字段信息

     * @access public

     * @return array

     */

    public function getTables($dbName='') {

        $result   =  $this->query("SELECT TABLE_NAME

            FROM INFORMATION_SCHEMA.TABLES

            WHERE TABLE_TYPE = 'BASE TABLE'

            ");

        $info   =   array();

        foreach ($result as $key => $val) {

            $info[$key] = current($val);

        }

        return $info;

    }



	/**

     * order分析

     * @access protected

     * @param mixed $order

     * @return string

     */

    protected function parseOrder($order) {

        return !empty($order)?  ' ORDER BY '.$order:' ORDER BY rand()';

    }



    /**

     * limit

     * @access public

     * @return string

     */

    public function parseLimit($limit) {

		if(empty($limit)) return '';

        $limit	=	explode(',',$limit);

        if(count($limit)>1)

            $limitStr	=	'(T1.ROW_NUMBER BETWEEN '.$limit[0].' + 1 AND '.$limit[0].' + '.$limit[1].')';

		else

            $limitStr = '(T1.ROW_NUMBER BETWEEN 1 AND '.$limit[0].")";

        return 'WHERE '.$limitStr;

    }



   /**

     * 更新记录

     * @access public

     * @param mixed $data 数据

     * @param array $options 表达式

     * @return false | integer

     */

    public function update($data,$options) {

        $this->model  =   $options['model'];

        $sql   = 'UPDATE '

            .$this->parseTable($options['table'])

            .$this->parseSet($data)

            .$this->parseWhere(!empty($options['where'])?$options['where']:'')

            .$this->parseLock(isset($options['lock'])?$options['lock']:false)

            .$this->parseComment(!empty($options['comment'])?$options['comment']:'');

        return $this->execute($sql);

    }



    /**

     * 删除记录

     * @access public

     * @param array $options 表达式

     * @return false | integer

     */

    public function delete($options=array()) {

        $this->model  =   $options['model'];

        $sql   = 'DELETE FROM '

            .$this->parseTable($options['table'])

            .$this->parseWhere(!empty($options['where'])?$options['where']:'')

            .$this->parseLock(isset($options['lock'])?$options['lock']:false)

            .$this->parseComment(!empty($options['comment'])?$options['comment']:'');

        return $this->execute($sql);

    }



    /**

     * 关闭数据库

     * @access public

     */

    public function close() {

        if ($this->_linkID){

            mssql_close($this->_linkID);

        }

        $this->_linkID = null;

    }



    /**

     * 数据库错误信息

     * 并显示当前的SQL语句

     * @access public

     * @return string

     */

    public function error() {

        $this->error = mssql_get_last_message();

        if('' != $this->queryStr){

            $this->error .= "\n [ SQL语句 ] : ".$this->queryStr;

        }

        trace($this->error,'','ERR');

        return $this->error;

    }

}